The following relates generally to wireless communication, and more specifically to overlapping code block groups (CBGs) for multiple codewords.
Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems (e.g., a Long Term Evolution (LTE) system, or a New Radio (NR) system). A wireless multiple-access communications system may include a number of base stations or access network nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE).
In some wireless communications systems, transport blocks (TBs) may be utilized for data transmissions. The TBs may be divided into smaller code blocks (CBs), which may be encoded with an error correcting code to add redundancy. Exploitation of this redundancy in the encoded information may improve the reliability of the message by allowing a receiving device to correct for bit errors that may occur (e.g., due to noise). Codewords may include a set of encoded CBs and each CB may include information bits and additional bits for error detection (e.g., cyclic redundancy check (CRC) bits, parity check bits, filler bits, etc.). A codeword may be transmitted over one or more spatial layers having a given modulation and coding scheme (MCS). Groups of CBs (e.g., of multiple codewords) may be transmitted concurrently or sequentially and when all of the CBs of a TB are received and decoded by the receiving device, the receiving device may provide feedback information to the transmitting device indicating whether the received TB has been successfully decoded. However, the feedback information may not include an indication of which CBs or groups of CBs were unsuccessfully decoded, which may cause the transmitting device to retransmit the entire TB in response even when a portion of the CBs were successfully decoded. More efficient techniques for feedback are desired.